The technology of the present disclosure relates generally to application modules for monitoring of signals in components of wireless distributed communications systems (WDCSs), including distributed antenna systems (DASs).
Wireless communication is rapidly growing, with ever-increasing demands for high-speed mobile data communication. As an example, local area wireless services (e.g., so-called “wireless fidelity” or “WiFi” systems) and wide area wireless services are being deployed in many different types of areas (e.g., coffee shops, airports, libraries, etc.). WDCSs communicate with wireless devices called “clients,” “client devices,” or “wireless client devices,” which reside within the wireless range or “cell coverage area” in order to communicate with an access point device. One example of a WDCS is a DAS. DASs are particularly useful to be deployed inside buildings or other indoor environments where client devices may not otherwise be able to effectively receive radio frequency (RF) signals from a source, such as a base station for example. Example applications where distributed antenna systems can be used to provide or enhance coverage for wireless services include public safety, cellular telephony, wireless local access networks (LANs), location tracking, and medical telemetry inside buildings and over campuses.
One approach to deploying a DAS involves the use of RF antenna coverage areas, also referred to as “antenna coverage areas.” Antenna coverage areas can be formed by remotely distributed remote antenna units (RAUs), which may also be referred to as remote units (RUs). The remote units each contain or are configured to couple to one or more antennas configured to support the desired frequency(ies) or polarization(s) to provide the antenna coverage areas. Antenna coverage areas can have a radius in the range from a few meters up to twenty meters as an example. Combining a number of remote units creates an array of antenna coverage areas. Because the antenna coverage areas each cover small areas, there typically may be only a few users (clients) per antenna coverage area. This arrangement generates a uniform high quality signal enabling high throughput supporting the required capacity for the wireless system users.
FIG. 1 illustrates an example of distribution of communications services in a WDCS. FIG. 1 illustrates distribution of communications services to coverage areas 10(1)-10(N) of a DAS 12, wherein ‘N’ is the number of coverage areas. These communications services can include cellular services, wireless services such as RFID tracking, WiFi, LAN, WLAN, and combinations thereof, as examples. The coverage areas 10(1)-10(N) may be remotely located. In this regard, the remote coverage areas 10(1)-10(N) are created by and centered on remote antenna units 14(1)-14(N) connected to a central unit 16 (e.g., a head-end controller (HEC) or head-end unit (HEU)). The central unit 16 may be communicatively coupled to a base station 18. In this regard, the central unit 16 receives downlink communications signals 20D from the base station 18 to be distributed to the remote antenna units 14(1)-14(N). The remote antenna units 14(1)-14(N) are configured to receive downlink communications signals 20D from the central unit 16 over a communications medium 22 to be distributed to the respective coverage areas 10(1)-10(N) of the remote antenna units 14(1)-14(N). Each remote antenna unit 14(1)-14(N) may include an RF transmitter/receiver (not shown) and a respective antenna 24(1)-24(N) operably connected to the RF transmitter/receiver to wirelessly distribute the communications services to client devices 26 within their respective coverage areas 10(1)-10(N). The remote antenna units 14(1)-14(N) are also configured to receive uplink communications signals 20U from the client devices 26 in their respective coverage areas 10(1)-10(N) to be distributed to the base station 18. The size of a given coverage area 10(1)-10(N) is determined by the amount of RF power transmitted by the respective remote antenna unit 14(1)-14(N), the receiver sensitivity, antenna gain and the RF environment, as well as by the RF transmitter/receiver sensitivity of the client device 26. Client devices 26 usually have a fixed RF receiver sensitivity, so that the above-mentioned properties of the remote antenna units 14(1)-14(N) mainly determine the size of their respective remote coverage areas 10(1)-10(N).
In the DAS 12 in FIG. 1, after installation and commissioning, a site walk is typically performed to analyze the data quality for optimization of the coverage areas 10(1)-10(N) created by the remote antenna units 14(1)-14(N). The site walk may involve activating the DAS 12 for the central unit 16 to receive the downlink communications signals 20D from the base station 18 for distribution to the remote antenna units 14(1)-14(N). Then, a service technician walks around the different coverage areas 10(1)-10(N) with a wireless communication device, such as a mobile phone or laptop computer, which may be referred to generally as a user equipment (UE), to receive the distributed downlink communications signals 20D from the remote antenna units 14(1)-14(N). The received downlink communications signals 20D can be reviewed and analyzed by personnel conducting the site walk to determine the quality of the coverage areas 10(1)-10(N), such as signal strength as an example. The DAS 12 may also be configured to generate alarms indicative of signal quality. Any quality issues in the DAS 12 can be identified and resolved. However, the context of the received downlink communications signals 20D is not known. For example, it is not known which received downlink communications signals 20D and/or how many communications bands are being distributed in the DAS 12.
An additional difficulty faced during a site walk is that the DAS 12 may operate to distribute signals for more than one carrier simultaneously. The conventional way of calibrating/diagnosing cellular signals in this scenario is to perform site walks with multiple UEs, where each UE is connected to a different carrier, and over-the-air scanners; after the site walk there is no on-site diagnostic equipment left on site for continuous monitoring of the on-going service signal changes. In order for the service technician's client device 26 to operate in a diagnostic mode, in which the client device 26 registers with the carrier network in order to get more detailed information, such as higher open systems interconnect (OSI) layer information, about the network signals, that client device 26 must have a carrier-specific subscriber identity module (SIM) card. A SIM card is not required by the client device 26 to operate in a scanning mode, during which the client device 26 does not register with a carrier but instead camps temporarily and can collect signal identification parameters and signal levels. However, having a SIM card allows the service technician's client device 26 to collect valuable information not available in scanning mode. As a result, a service technician performing a site walk in a DAS 12 that supports multiple carriers must possess multiple client devices 26, one client device 26 for every carrier being supported within the DAS 12. Some cellular providers/OEM vendors now offer stand-alone equipment that consists of multiple UEs to monitor different signal types. Such equipment is located at known location such as different zones in a stadium to continuously monitor the quality of service (QoS) or quality of experience (QoE) of the cellular signals. However, such equipment merely contains multiple, separate UEs to monitor different service providers, each UE containing a carrier-specific SIM. Installation, maintenance, and operation of these units are cost prohibitive in nature due to the cumbersome hardware and maintenance of the multiple SIMs.
No admission is made that any reference cited herein constitutes prior art. Applicant expressly reserves the right to challenge the accuracy and pertinency of any cited documents.